Comet Holmes
Comet 17P/Holmes is a short-period comet that was discovered in 1892. With an orbit that only (a word which must be read within its celestial context) takes it past the orbit of Mars, it comes through the neighborhood every seven years. It's back, but a couple of days ago it abruptly went from magnitude 17-about the brightness of Pluto, 25,000 times too dim for the naked eye-to a magnitude of about 2.5, which puts it on par with many moderately bright stars in the sky. It's now the brightest comet in the sky since Comet Hale-Bopp in 1997.
The likely reason for the sudden brightness is outgassing, caused by a rise in temperature as the comet approaches the sun. That means it will probably only be this bright for a short time before it disappears again. You can see it tonight in the northeast sky, about 1.5 hand's breadths (at arm's length) up and to the left of the waning gibbous moon. Look for a "star" that's visibly fuzzier than actual stars.
Tonight, it forms the lower left point of an isosceles triangle with Mirfak and Delta Persei in the constellation Perseus. It will move towards the top star (Mirfak) in the coming days, but there's no telling when it will vanish. If you want to see it, don't wait!
ETA: I can't really take sky photos with my big, clumsy Dobsonian reflector, but this photo gives you a good idea of what I see in my eyepiece. Just imagine it's bluish-grey instead of yellowish-green. :)
The likely reason for the sudden brightness is outgassing, caused by a rise in temperature as the comet approaches the sun. That means it will probably only be this bright for a short time before it disappears again. You can see it tonight in the northeast sky, about 1.5 hand's breadths (at arm's length) up and to the left of the waning gibbous moon. Look for a "star" that's visibly fuzzier than actual stars.
Tonight, it forms the lower left point of an isosceles triangle with Mirfak and Delta Persei in the constellation Perseus. It will move towards the top star (Mirfak) in the coming days, but there's no telling when it will vanish. If you want to see it, don't wait!
ETA: I can't really take sky photos with my big, clumsy Dobsonian reflector, but this photo gives you a good idea of what I see in my eyepiece. Just imagine it's bluish-grey instead of yellowish-green. :)